Hi Kim-
One thing you can check (and many hear don't agree with this approach ... because it is automated), is to run each of your domain names through the GoDaddy Domain Name Value and Appraisal. Sure there is no online (or any other) appraisal that is going to tell you how much you can sell your domain names for, but at least this one will tell you whether you have a name that may be worth something (based on similar names that have sold on GoDaddy) versus being in the other 99% where you have 'brandables" or other names with bad keywords, etc.
Once you run each of the 140 names you have through the GoDaddy appraisal, how many of them come back with a number over $2,500?
Anything under that, I have found, means there is no current market for the name and you will need to work hard to get it sold for any profit - even if it says $1,500 - there are thousands of names that come back like that but aren't really marketable.
If you have names that might have future potential and you want to hold on to them for a while, that is different. There are many here who buy names on speculation - early bitcoin name investors immediately come to mind - that have made money on names that aren't worth much when first purchased, but gain in value based on popularity of the keyword/name.